1. Field of the Invention
The invention relates to a method for monitoring fluid pressure in a well and to a retrievable pressure assembly for use in the method.
2. Background of the Art
U.S. Pat. No. 6,464,004 discloses installing a pressure monitoring assembly in a side pocket of a production tubing in a well, such that the assembly can be easily installed and retrieved into and from the side pocket by means of a kickover tool that is suspended from a wireline.
The known assembly is configured to monitor the pressure in an annulus between the production tubing and well casing by a pressure gauge, which is arranged in an annular space between the housing of the pressure sensing assembly between a pair of annular seals that are mounted on the housing, which space is in fluid communication with the annulus via an opening in the wall of the side pocket.
The known assembly may also be configured to monitor the pressure in a tubing below an electrical submersible pump, generally known as an ESP, in a well by arranging a pressure monitoring assembly in a side pocket of a production tubing above the ESP and by providing a bypass conduit which is at its lower end connected to the interior of the tubing below the ESP and at its upper end connected to the opening in the wall of the side pocket that is located between the annular seals of the pressure sensing assembly.
A disadvantage of the known pressure sensing assembly is that the presence of a bypass conduit makes the assembly complex and fragile. A further disadvantage is that the known pressure sensing assembly is not configured to monitor the pressure difference across the ESP or other pump.
U.S. Pat. No. 6,568,478 discloses a gas-lift valve with a venturi which stabilises the flux of lift gas injected from the annulus into the crude oil production tubing. The known valve may be retrievably inserted in a side pocket that provides fluid communication between the interior of the production tubing and the surrounding annulus.